First of all water it....water it until water runs out the bottom and then water some more....and then again.
your plant has dried out and you will have to re wet the root ball to get it to hold water again.
In a week or 10 days after you have kept it moist yous hould see some new growth, then you can cut the dead stuff off.
You can't even once allow them to get dry once....they have to be well watered every day and often twice if its' hot and dry. Rain won't do the job...has to be a hose and water until the water runs freely out the bottom of the pot.
Linda C

Linda is 100% right. And I also think these outgrow their pots pretty fast and need to be potted up another size or two about now. A pain in the neck but it beats losing them.

Thanks Linda & Ginny,

You are both exactly right. Roots are so big there's hardly any growing medium left to retian any water in the first place. And we've been gone weekends and I return to the brown basket. I'll repot and give it another go. Poor thing!

Hey, guess what? I cut the whole ugly thing way back to 5 inch stubs (the stems were verrrry long before... 18 inches?). And it's leafing out all green! Looks great. DH calls the back lamp (where it's hanging) the Calibrachoa Hospital. If it recovers, it will be allowed back to the front. ;)